The George Marshall Store Gallery is located in a smallish, pale yellow building next to the York River. Built in the 1860s and now one of many official Museums of Old York, you'd be forgiven for assuming its significance was purely historical. Anyone setting foot inside the GMSG can tell the place is hardly inert. Now in its 17th year serving the contemporary-art needs of the greater Seacoast, the gallery opens its season with "Momentum X," the tenth in a series of mixed media juried group shows.

The exhibit revolves around the work of the highest-placing artists to apply for the Piscataqua Region Artists Enhancement Grant, an initiative of the New Hampshire Charitable Foundation, but the four entries (plus one, we'll get to that later) reveal such diverse processes and expressions that "Momentum" becomes a satisfying, ruminative one all its own.

North Berwick artist Kim Bernard demolishes one of the fundamental rules of gallery art: that it must not be touched. Her kinesthetic, wall-mounted sculpture "Quantum Revival" requires the playful, awkward tinkering of its viewers to set it into motion. When performed, several suspended encaustic weights sway in harmonious counterpoint, moving in and out of sync over a 60-second cycle. Marrying mathematics, gravity, repetition, and levity (as in humor), Bernard is becoming well known for this sort of thing; "Quantum Revival" will be immediately familiar to those who attended last year's Biennial at the Portland Museum of Art.

While Bernard's piece examines the passing of time in micro, Lauren Gillette's equally magnificent installation on the opposite wall expands it as much as possible. Inspired by a literary motif found in a contemporary novel by Paul Harding, the installation is a thoughtful, disorienting manifestation of a postmodern storytelling technique, encouraging reflection while working within a contemporary aesthetic. Following the lead of one of Harding's characters, Gillette petitioned internationally for volunteers to summarize their lives in a mere five lines of text. The results she etched into three rows of mirror plates set at slightly off angles — you can see your reflection, but only in fragments — and marked the stories with only their authors' age and first name.

To its benefit, Seacoast painter Rose Umerlik's work seems to dance around ready description. The bulk of it hangs in the gallery's floodlit back room, where the conversations her delicate lines and amorphous bodies of color engage in are glowingly articulate. Nonrepresentational, emotive, and not always glamorous, Umerlik's paintings are unexpectedly rewarding, like the quiet person at a party whose conversation you're later surprised you best recall.

With these emotional and universal themes, Lisa Grey's assemblages of materials extracted from the nearby dismantling of the Memorial Bridge make a nice, tangible touch. Her "Memorial" takes a fragmented photo montage of bridge detritus rendered onto an 80-by-23-inch strip of translucent silk organza and suspends it before another silk surface, on which Grey has undertaken a laborious process of rust printing. Several small frames of arranged materials the artist found near the bridge border the piece while observing her history as a textilist, but "Memorial" is the most memorable among them.

UNMASKING AFRICAN RELICS | February 26, 2014 An evocative, transportive exhibit of icons, artifacts, and spirit masks from some of the many, many cultures and “kingdoms” of West Africa, what is now Cameroon and Nigeria.

THE TEQUILA ODYSSEY | February 20, 2014 Each of the city’s drinking establishments has its roots in some primordial myth.

TRUE EFFIN' ARTISTRY | February 20, 2014 Mousa is the new recording alias of Vince Nez, a/k/a Aleric Nez, the name by which he released a nimble, unpredictable record in late 2010.

THE STATE OF SEA SALT | February 12, 2014 A surfeit of salt manufacturers have cropped up in the state over the last few years.

NOT YOUR AUNTIE'S DOOM | February 06, 2014 Sure, it may be Latin for “forest of trees,” but Sylvia more readily conjures some wiseacre aunt, not a burly group of veteran musicians trying to carve new notches in well-trod forms of heavy metal.